1. Field of Invention
The present invention relates to a tricycle and, more particularly, to an inexpensive tricycle that includes only one directly steered rear wheel and a free rear wheel.
2. Related Prior Art
As disclosed in Taiwanese Patent Nos. M364645 and M366500, a tricycle includes a frame for supporting a front wheel and two rear wheels. The typical tricycle further includes a steering mechanism that includes a handlebar and two linkage units. Each of the linkage units connects a corresponding one of the rear wheels to the handlebar. However, the use of two linkage units inevitably renders the tricycle expensive.
U.S. Pat. No. 8,256,784 discloses a tricycle including a frame 102, a front wheel assembly 110, a front steering mechanism 120, two rear wheel assemblies 150 and at least one rear steering mechanism 470. The front steering mechanism 120 is adapted to steer the front wheel assembly 110. Each rear wheel assembly 150 includes a casing 151a (151b), a rear wheel 152a (152b), a rear wheel axle 153a (153b) and a coupling member 154a (154b). Each casing 151a (151b) holds a corresponding rear wheel axle 153a (153b) that supports a corresponding rear wheel 152a (152b). Each casing 151a (151b) is connected to an end 132 (134) of a crossbar 130 of the frame 102 via a corresponding coupling member 155a (155b). However, the rear casing 151a cannot smoothly follow the rear casing 151b if the rear steering mechanism 470 is only connected to the rear casing 151b since the axis of each coupling member 155a (155b) intersects the axis of the corresponding rear wheel axle 153a (153b).
The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.